A、Buy a new watch. B、Go to bed earlier. C、See a doctor. D、Change his job. B推理题。从对话中可以得知男士将在下周结束课题的研究，可以恢复到正常的作息，由此可以判断他可能会早点上床入睡

M: I’m so tired, I can’t see straight.
W: You’ve been tired a lot lately, haven’t you?
M: Well,(5)for the last few weeks, I have had to stay up most of the night to observe star configurations for a project for my astronomy class. It’s awful! No matter what time I go to bed, I always wake up at 6 a.m. That’s the time I usually get up.
W: (7)Your biological rhythms probably haven’t been adjusted to your new schedule. I’ve read that some people have a lot of trouble when their sleep rhythm is so interrupted. Even sleeping pills don’t help them.
M: I know.(6)In fact I’ve heard there are now several special treatment centers for sleep disorders across the country. Some people sleep too little. Some people sleep too much. Some walk in their sleep.
W: I’d like to find out how they treat problems like that. Maybe you should go to one of those centers.
M: Not me.(8)After next week, my project will be finished and I’ll go back to my regular hours. Now I know for sure that I don’t want to be an astronomer.
Questions 5 to 8 are based on the conversation you have just heard.
5. What has the man not been able to do recently?
6. What remedy did the man hear about as an aid to helping people sleep?
7. Why does the man feel exhausted?
8. What will the man probably do next week?